To establish the natural history of individuals who have had operative repair of coarctation of the aorta, we will enroll all patients operated at the U of MN between 1952-1972. Hypertension is the most important risk factor associated with significant morbidity and mortality among patients after operative repair of coarctation of the aorta. Understanding the possible mechanisms underlying hypertension and its hemodynamic consequences may help us develop appropriate guidelines for evaluation and treatment of this important disease.